Articles | Volume 18, issue 18
https://doi.org/10.5194/gmd-18-6167-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-18-6167-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
A new vertical reduction model for enhancing the interpolation accuracy of VMF1/VMF3 tropospheric delay products
School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
Kefei Zhang
CORRESPONDING AUTHOR
School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
Satellite Positioning for Atmosphere, Climate and Environment (SPACE) Research Centre, RMIT University, Melbourne VIC 3001, Australia
Dantong Zhu
College of Surveying and Geo-Informatics, North China University of Water Resources and Electric Power, Zhengzhou 450000, China
Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection, College of Resources and Environment, Linyi University, Linyi 276000, China
Xuexi Liu
School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
Dongsheng Zhao
School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
Minghao Zhang
School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
Suqin Wu
School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
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In GPS or Global navigation satellite systems (GNSS) meteorology, precipitable water vapor (PWV) at a station is obtained from a conversion of the GNSS signal zenith wet delay (ZWD) using a conversion factor which is a function of weighted mean temperature (Tm) over the site. We developed a new global grid-based empirical Tm model using ERA5 reanalysis data. The model-predicted Tm value has significance for applications needing real-time or near real-time PWV converted from GNSS signals.
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The zenith hydrostatic delay (ZHD) derived from blind models are of low accuracy, especially in mid- and high-latitude regions. To address this issue, the ratio of the ZHD to zenith total delay (ZTD) is firstly investigated; then, based on the relationship between the ZHD and ZTD, a new ZHD model was developed using the back propagation artificial neural network (BP-ANN) method which took the ZTD as an input variable. The model outperforms blind models.
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In GPS or Global navigation satellite systems (GNSS) meteorology, precipitable water vapor (PWV) at a station is obtained from a conversion of the GNSS signal zenith wet delay (ZWD) using a conversion factor which is a function of weighted mean temperature (Tm) over the site. We developed a new global grid-based empirical Tm model using ERA5 reanalysis data. The model-predicted Tm value has significance for applications needing real-time or near real-time PWV converted from GNSS signals.
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Short summary
A new method has been developed to more accurately adjust atmospheric delay data for use in satellite positioning, especially in areas with large height differences. By using long-term weather data and testing with global observation stations, the new method significantly improves accuracy compared to traditional approaches. This can benefit applications such as precise positioning and weather monitoring using navigation satellite signals.
A new method has been developed to more accurately adjust atmospheric delay data for use in...